摘要:
Keys (e.g., decryption key, authentication key) are stored in a non-volatile memory of a display unit. The keys are retrieved in encrypted form into an integrated circuit. The integrated circuit decrypts the keys and uses the keys. As the keys are available in decrypted form only within the integrated circuit and potentially only during use, the keys may not be available to unauthorized third parties.
摘要:
Keys (e.g., decryption key, authentication key) are stored in a non-volatile memory of a display unit. The keys are retrieved in encrypted form into an integrated circuit. The integrated circuit decrypts the keys and uses the keys. As the keys are available in decrypted form only within the integrated circuit and potentially only during use, the keys may not be available to unauthorized third parties.
摘要:
A multimedia system includes an audio/video decompresser/decoder for decompressing/decoding a compressed/encoded audio/video data stream in order to generate video images for display on a display device and to generate audio signals for audible reproduction. The multimedia system includes an integrated system and video decoder that has a novel memory controller and a novel method for displaying complete decoded/decompressed video frames on a display device without tearing. By use of selective storage of decoded/decompressed video frames in memory, tearing is prevented but information for predicting motion of a video segment is preserved.
摘要:
A method and apparatus for automatically synchronizing the polarity of video signals generated by a graphics controller card to a display monitor is described. The present invention includes hardware circuitry comprising a storage unit, a detection unit, a selection unit that store, detect, and select input video signals, particularly a vertical and a horizontal synchronization signals, with the same or different polarity that are received from the graphics controller to a display monitor. The present invention synchronizes the polarity of input vertical and horizontal synchronization signals from the graphics controller prior to transmitting the sync signals to the display monitor. The detect and selection circuits of the present invention enable polarity of input sync signals to be synchronized without the use of software as practiced in the prior art.
摘要:
A multimedia system includes an audio/video decompresser/decoder for decompressing/decoding a compressed/encoded audio/video data stream in order to generate video images for display on a display device and to generate audio signals for audible reproduction. The multimedia system includes an integrated system and video decoder that has a novel memory controller and a novel method for displaying complete decoded/decompressed video frames on a display device without tearing. By use of selective storage of decoded/decompressed video frames in memory, tearing is prevented but information for predicting motion of a video segment is preserved.
摘要:
A circuit and method for increasing the processing efficiency of texture map data requests within a 3D subunit of a computer controlled graphics display system. The 3D graphics display subsystem includes a polygon engine, a texture map engine and a pixel pipeline. The texture map engine contains a texture map data access (TDA) circuit having a cache controller with a computer readable cache memory for containing recently used texture maps stored in (u,v) coordinate space. The cache controller is limited in handling only n cache miss operations simultaneously. In one embodiment, n is 1. The TDA circuit also contains a texture map address (TMA) FIFO memory unit for storing texture map addresses associated with texture data requests that hit or missed in the cache memory unit. Since the cache controller handles up to n misses, the texture engine stalls when the (n+1).sup.th unprocessed texture request miss is encountered. Therefore, the TMA FIFO at any time contains at most n miss addresses therein. Processing efficiency is increased when a miss is encountered but the TMA FIFO contains unprocessed hit addresses. At this time, simultaneously with the cache controller fetching the texture data for the missed address, it can also advantageously: (1) supply data from the cache memory for the previously encountered and stored hit addresses; and (2) accept new hit addresses into the TMA FIFO thereby effectively avoiding a texture engine stall. This is quite unlike the prior art systems which process no hit addresses upon a texture miss but rather stall the texture engine.
摘要:
A decoder is disclosed for decoding MPEG video bitstreams encoded in any color space encoding format and outputting the decoded video bitstream to different sized windows. Both MPEG decompression and color space decoding and conversion are performed on the bitstreams within the same decoder. The disclosed decoder may be programmed to output the decoded video bitstream in any of three primary color space formats comprising YUV 4:2:0, YUV 4:2:2, and YUV 4:4:4. The decoder may also output the decoded bitstream to different sized windows using Discrete Cosine Transform (DCT) based image resizing.
摘要:
An automatic bus identification circuit is provided in a device to reliably detect system bus type on power up despite fluctuations in supply voltage. A system bus type signal is received over a multi-function input line at a first input and a reset signal received over a set line at a second input. A bus type identification circuitry is provided to latch the system bus type signal upon power up and continuously output this signal as a system bus type identification signal. To prevent the influence of disturbances in the power supply upon power-up, a flip-flip is provided to output a logic signal in response to a system reset signal. The flip-flop is configured with a strong-N type inverter to insure that the flip-flop will be set into a grounded state as power is applied to the circuit, despite the influence of transient power supply voltages.